Flame-resistant polycarbonate blends

ABSTRACT

A thermoplastic molding composition that contains a resinous blend with phosphonate amine is disclosed. The resinous blend contains polycarbonate and a graft polymer having a graft substrate rubber selected from among silicone, EP(D)M and acrylate rubbers. The composition exhibits exceptional flame resistance and good mechanical properties such as stress cracking resistance and ease of flow while exhibiting high heat resistance.

The present invention provides blends which contain phosphonate aminesand are based on polycarbonate and graft polymers selected from thegroup consisting of silicone, EP(D)M and acrylate rubbers as graftsubstrate, which have exceptional flame resistance and very goodmechanical properties such as stress cracking resistance or ease of flowwhile exhibiting high heat resistance.

U.S. Pat. Nos. 4,073,767 and 5,844,028 describe cyclic phosphoruscompounds including phosphorinane rings as suitable flame retardants forpolyurethanes, polycarbonates, polyesters and polyamides. In U.S. Pat.No. 4,397,750, specific cyclic phosphonate esters are described asefficient flame retardants for polypropylene and other polyolefins. U.S.Pat. No. 5,276,066 and U.S. Pat. No. 5,844,028 describe specific(1,3,2-dioxaphosphorinanemethane) amines which are suitable flameretardants for polyurethanes, polyesters, styrene polymers, PVC, PVAc orpolycarbonate.

U.S. Pat. No. 3,505,431, FR-P 1 371 139, U.S. Pat. No. 3,711,577, U.S.Pat. No. 4,054,544 describe acyclic triphosphonate amines, some of whichare halogenated.

EP-A 0 640 655 describes moulding compositions made from aromaticpolycarbonate, styrene-containing copolymers and graft polymers whichcan be made flame resistant with monomeric and/or oligomeric phosphoruscompounds.

EP-A 0 363 608 describes flame resistant polymer mixtures made fromaromatic polycarbonate, styrene-containing copolymers or graftcopolymers and also oligomeric phosphates as a flame resistant additive.For many applications such as, for example, in the internal sections ofhousings, the heat resistance of these mixtures is often inadequate.

U.S. Pat. No. 5,061,745 describes polymer mixtures made from aromaticpolycarbonate. ABS graft polymers and/or styrene-containing copolymersand with monophosphates as flame retardant additives. For the productionof thin-walled housing parts, the level of stress cracking resistance ofthese mixtures is often inadequate.

The object of the present invention is the provision of polycarbonateblends with exceptional flame resistance and exceptional mechanicalproperties such as stress cracking resistance, processability and easeof flow. This range of properties is demanded in particular forapplications in the data processing sector such as, for example, forhousings of monitors, printers, copiers, etc.

It has now been found that blends based on polycarbonate and graftpolymers selected from the group consisting of silicone, EP(D)M andacrylate rubbers which contain phosphonate amines have the requiredproperties.

The invention therefore provides blends which contain polycarbonateand/or polyestercarbonate, at least one rubber-elastic graft polymerselected from the group consisting of silicone, EP(D)M and acrylaterubbers as graft substrate and 0.1 to 30 parts by weight (with respectto the entire mixture) of phosphonate amine of the formula (I)

A_(3-y)—N—B_(y)  (I),

in which

A represents a group of the formula (IIa)

R¹ and R², independently, represent an unsubstituted or substitutedC₁-C₁₀ alkyl group or an unsubstituted or substituted C₆-C₁₀ aryl group,

R³ and R⁴, independently, represent an unsubstituted or substitutedC₁-C₁₀ alkyl group or an unsubstituted or substituted C₆-C₁₀ aryl groupor

R³ and R⁴ together represent an unsubstituted or substituted C₃-C₁₀alkylene group,

y has the numerical value 0,1 or 2 and

B independently, represents hydrogen, an optionally halogenated C₂-C₈alkyl group, or an unsubstituted or substituted C₆-C₁₀ aryl group.

The invention preferably provides thermoplastic moulding compositions(blends) containing

A) 40 to 99, preferably 60 to 98.5 parts by wt. of an aromaticpolycarbonate and/or polyestercarbonate.

B) 0.5 to 60, preferably 1 to 40, in particular 2 to 25 parts by wt. ofat least one rubber-elastic graft polymer, selected from the groupconsisting of silicone, EP(D)M and acrylate rubbers as graft substrate,

C) 0 to 45, preferably 0 to 30, in particular 2 to 25 parts by wt. of atleast one thermoplastic polymer, selected from the group consisting ofvinyl (co)polymers and polyalkylene terephthalates,

D) 0.1 to 30 parts by wt., preferably 1 to 25 parts by wt., inparticular 2 to 20 parts by wt. of phosphonate amine of the formula (I)

A_(3-y)—N—B_(y)  (I),

 in which

 A, B and y are defined in the same way as above, and

E) 0 to 5, preferably 0.1 to 3, in particular 0.1 to 1 parts by wt.,quite specifically 0.1 to 0.5 parts by wt. of a fluorinated polyolefin,

wherein the sum of the parts by weight of all the components is 100.

Component A

Aromatic polycarbonates and/or aromatic polyestercarbonates suitable foruse according to the invention in accordance with component A are knownfrom the literature or can be prepared by methods known from theliterature (to prepare aromatic polycarbonates see, for example,Schnell, “Chemistry and Physics of Polycarbonates”, IntersciencePublishers, 1964 and DE-AS 1 495 626, DE-OS 2 232 877, DE-OS 2 703 376,DE-OS 2 714 544, DE-OS 3 000 610, DE-OS 3 832 396; to prepare aromaticpolyestercarbonates see, for example, DE-OS 3 077 934).

Polycarbonates are prepared, for example, by reacting diphenols withcarbonic acid halides, preferably phosgene and/or with aromaticdicarboxylic acid dihalides, preferably benzenedicarboxylic aciddihalides, by the phase interface method, optionally using chainstoppers; for example monophenols, and optionally using trifunctional ormore than trifunctional branching agents, for example triphenols ortetraphenols.

Diphenols for preparing aromatic polycarbonates and/or aromaticpolyestercarbonates are preferably those of the formula (III)

wherein

A represents a single bond, a C₁-C₅ alkylene, C₂-C₅ alkylidene, C₅-C₆cycloalkylidene, —O—, —SO—, -CO—, —S—, —SO2, or C₆-C₁₂ arylene group, towhich further aromatic rings, optionally containing heteroatoms, may becondensed,

 or a group of the formula (IV) or (V)

B each represent a C₁-C12 alkyl group, preferably methyl or a halogen,preferably chlorine and/or bromine,

x each represent, independently, 0,1 or 2,

p is 1 or 0 and

R⁷ and R⁸ can be chosen independently for each X¹ and represent,independently, hydrogen or a C₁-C₆ alkyl group, preferably hydrogen,methyl or ethyl,

X¹ represents carbon and

m is an integer from 4 to 7, preferably 4 or 5, with the proviso that R⁷and R⁸ are simultaneously alkyl groups on at least one X¹ atom.

Preferred diphenols are hydroquinone, resorcinol, dihydroxydiphenols,bis-(hydroxyphenyl)-C₁-C₅-alkanes,bis-(hydroxyphenyl)-C₅-C₆-cycloalkanes, bis-(hydroxyphenyl)-ethers,bis-(hydroxyphenyl)-sulfoxides, bis-(hydroxyphenyl)-ketones,bis-(hydroxyphenyl)-sulfones andα,α-bis-(hydroxyphenyl)-diisopropyl-benzenes and their ring-brominatedand/or ring-chlorinated derivatives.

Particularly preferred diphenols are 4,4′-dihydroxydiphenyl,bisphenol-A, 2,4-bis-(4-hydroxyphenyl)-2-methylbutane,1,1-bis-(4-hydroxyphenyl)-cyclohexane,1,1-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane,4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxydiphenyl sulfone and theirdi- and tetrabrominated or chlorinated derivatives such as, for example,2,2-bis-(3-chloro-4-hydroxyphenyl)-propane,2,2-bis-(3,5-dichloro-4-hydroxyphenyl)-propane or2,2-bis-(3,5-dibromo-4-hydroxyphenyl)-propane.

2,2-bis-(4-hydroxyphenyl)-propane (bisphenol-A) is particularlypreferred.

The diphenols may be used individually or as any mixture thereof.

The diphenols are known from the literature or are obtainable by methodsknown from the literature.

Chain stoppers which are suitable for preparing thermoplastic, aromaticpolycarbonates are, for example, phenol, p-chlorophenol,p-tert.-butylphenol or 2,4,6-tribromophenol, but also long-chainalkylphenols such as 4-(1,1,3,3-tetamethylbutyl)-phenol in accordancewith DE-OS 2 842 005 or monoalkylphenols or dialkylphenols with a totalof 8 to 20 carbon atoms in the alkyl substituents, such as3,5-tert.-butylphenol, p-iso-octylphenol, p-tert-octylphenol,p-dodecylphenol and 2-(3,5-dimethylheptyl)-phenol and4-(3,5-dimethylheptyl)-phenol. The amount of chain stoppers to be usedis in general between 0.5 mol % and 10 mol %, with respect to the molarsum of each of the diphenols used.

The thermoplastic, aromatic polycarbonates have mean weight-averagemolecular weights (M_(w), measured, for example, by ultracentrifuge orlight scattering measurements) of 10 000 to 200 000, preferably 20 000to 80 000.

The thermoplastic, aromatic polycarbonates may be branched in a knownmanner, in fact preferably by incorporating 0.05 to 2.0 mol %, withrespect to the sum of the diphenols used, of trifunctional or more thantrifunctional compounds, for example those with three or more phenolicgroups.

Both homopolycarbonates and also copolycarbonates are suitable. Toprepare copolycarbonates in accordance with component A according to theinvention, 1 to 25 wt. %, preferably 2.5 to 25 wt. % (with respect tothe total amount of diphenols used) of polydiorganosiloxanes withhydroxy-aryloxy terminal groups may also be used. These are known (see,for example, U.S. Pat. No. 3,419,634) or can be prepared by methodsknown from the literature. The preparation ofpolydiorganosiloxane-containing copolycarbonates is described, forexample, in DE-OS 3 334 782.

Preferred polycarbonates, in addition to bisphenol-A homopolycarbonates,are the copolycarbonates of bisphenol-A with up to 15 mol %, withrespect to the molar sum of diphenols, other than the diphenolsmentioned as preferred or particularly preferred, in particular2,2-bis-(3,5-dibromo-4-hydroxyphenyl)-propane.

Aromatic dicarboxylic acid dihalides for preparing aromaticpolyestercarbonates are preferably the diacid dichlorides of isophthalicacid, terephthalic acid, diphenylether-4,4′-dicarboxylic acid andnaphthalene-2,6-dicarboxylic acid.

Mixtures of the diacid dichlorides of isophthalic acid and terephthalicacid in a ratio between 1:20 and 20:1 are particularly preferred.

When preparing polyestercarbonates, a carbonic acid halide, preferablyphosgene, is also used as a bifunctional acid derivative.

Suitable chain stoppers for use when preparing aromaticpolyestercarbonates are, in addition to the monophenols mentioned above,their chlorocarbonates and also the acid chlorides of aromaticmonocarboxylic acids, which may optionally be substituted by C₁-C₂₂alkyl groups or by halogen atoms, and also aliphatic C₂-C₂₂monocarboxylic acid chlorides.

The amount of each chain stopper is 0.1 to 10 mol %, with respect, inthe case of phenolic chain stoppers, to the moles of diphenols and, inthe case of monocarboxylic acid chloride chain stoppers, to moles ofdicarboxylic acid dichlorides.

The aromatic polyestercarbonates may also contain copolymerised aromatichydroxycarboxylic acids.

The aromatic polyestercarbonates may be either linear or branched in aknown manner (with reference to this point, see also DE-OS 2 940 024 andDE-OS 3 007 934).

Branching agents which may be used are, for example trifunctional ormore than trifunctional carboxylic acid chlorides such as trimesic acidtrichloride, cyanuric acid trichloride,3,3′,4,4′-benzophenone-tetracarboxylic acid tetrachloride,1,4,5,8-naphthalenetetracarboxylic acid tetrachloride or pyromelliticacid tetrachloride, in amounts of 0.01 to 1.0 mol % (with respect to thedicarboxylic acid dichlorides used) or trifunctional or more thantrifunctional phenols such as phloroglucinol,4,6-dinethyl-2,4,6-tri-(4-hydroxyphenyl)-hept-2-ene,4,4dimethyl-2,4,6-tri-(4-hydroxyphenyl)-heptane,1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-hydroxyphenyl)-ethane,tri-(4-hydroxyphenyl)-phenylmethane,2,2-bis-[4,4-bis-(4-hydroxyphenyl)-cyclohexyl]-propane,2,4-bis-(4-hydroxyphenylisopropyl)-phenol,tetra-(4-hydroxyphenyl)-methane,2,6-bis-(2-hydroxy-5-methylbenzyl)4-methylphenol,2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)-propane,tetra-(4-[4-hydroxyphenylisopropyl]-phenoxy)-methane,1,4-bis-[4,4′-dihydroxytriphenyl)-methyl]-benzene, in amounts of 0.01 to1.0 mol %, with respect to the diphenols used. Phenolic branching agentsmay be initially introduced with the diphenols, acid chloride branchingagents may be introduced together with the acid dichlorides.

In the thermoplastic, aromatic polyestercarbonates, the proportion ofcarbonate structural units may be any value at all. The proportion ofcarbonate groups is preferably up to 100 mol %, in particular up to 80mol %, especially up to 50 mol %, with respect to the sum of estergroups and carbonate groups. Both the ester fraction and the carbonatefraction of the aromatic polyestercarbonates may be present in the formof blocks or may be distributed statistically within the polycondensate.

The relative solution viscosity (η_(rel)) of the aromatic polycarbonatesand polyester carbonates is in the range 1.18 to 1.4, preferably 1.22 to1.3 (measured using solutions of 0.5 g of polycarbonate orpolyestercarbonate in 100 ml of methylene chloride solution at 25° C.).

The thermoplastic, aromatic polycarbonates and polyestercarbonates maybe used separately or as any mixture with each other.

Component B

Component B contains one or more rubber-elastic graft polymers chosenfrom the group of silicone, acrylate and EP(D)M rubbers as graftsubstrate.

Component B preferably contains one or more graft polymers of

B.1 5 to 95, preferably 20 to 80, in particular 30 to 80 wt. % of atleast one vinyl monomer on

B.2 95 to 5, preferably 80 to 20, in particular 70 to 20 wt. % of one ormore graft substrates with glass transition temperatures of <10° C.,preferably <0° C., in particular <−20° C. selected from the groupconsisting of silicone, acrylate and EP(D)M rubbers. Graft substrate B.2generally has an average particle size (d₅₀ value) of 0.05 to 5 μm,preferably 0.10 to 0.5 μm, in particular 0.20 to 0.40 μm.

Monomers B.1 are preferably mixtures of

B.1.1 50 to 99, preferably 60 to 80 parts by wt. of vinyl aromaticcompounds and/or ring-substituted vinyl aromatic compounds (such as, forexample, styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene)and/or (C₁-C₈)alkyl methacrylates (such as e.g. methyl methacrylate,ethyl methacrylate) and

B.1.2 1 to 50, preferably 40 to 20 parts by wt. of vinyl cyanides(unsaturated nitrites such as acrylonitrile and methacrylonitrile)and/or (C₁-C₈)alkyl(meth)acrylates (such as e.g. methyl methacrylate,n-butyl acrylate, t-butyl acrylate) and/or derivatives (such asanhydrides and imides) of unsaturated carboxylic acids (for examplemaleic anhydride and N-phenyl-maleic imide).

Preferred monomers B.1.1 are selected from at least one of the monomersstyrene, α-methylstyrene and methyl methacrylate, preferred monomersB.1.2 are selected from at least one of the monomers acrylonitrile,maleic anhydride and methyl methacrylate.

Particularly preferred monomers are B.1.1 styrene and B.1.2acrylonitrile.

Suitable silicone rubbers B.2 according to the invention consist largelyof the structural units

wherein

R¹¹ and R¹² may be identical or different and represent C₁-C₆ alkyl orcycloalkyl or C₆-C₁₂ aryl groups.

Preferred silicone rubbers B.2 are particulate with an average particlediameter d₅₀ of 0.09 to 1 μm, preferably 0.09 to 0.4 μm, and a gelcontent of more than 70 wt. %, in particular 73 to 98 wt. % and areobtainable from

1) dihalo-organosilanes

2) 0 to 10 mol %, with respect to 1), of trihalosilanes and

3) 0 to 3 mol %, with respect to 1), of tetrahalosilanes and

4) 0 to 0.5 mol %, with respect to 1) of halotriorganosilanes,

wherein the organic groups in compounds 1), 2) and 4) are

α) C₁-C₆ alkyl or cyclohexyl, preferably methyl or ethyl,

β) C₆-C₁₂ aryl, preferably phenyl,

γ) C₁-C₆ alkenyl, preferably vinyl or allyl,

δ) mercapto-C₁-C₆ alkyl, preferably mercaptopropyl,

with the proviso that the sum (γ+δ) is 2 to 10 mol %, with respect toall the organic groups in compounds 1), 2) and 4), and the molar ratioγ:δ=3:1 to 1:3, preferably 2:1 to 1:2.

Preferred silicone rubbers B.2 contain at least 80 mol % of methylgroups as organic groups. The terminal group is generally adiorganyl-hydroxyl-siloxy unit, preferably a dimethylhydroxysiloxy unit.

Preferred silanes 1) to 4) for preparing silicone rubbers B.2 containchlorine as halogen substituents.

“Obtainable” means that the silicone rubber B.2 does not have to beprepared solely from the halogenated compounds 1) to 4). It is intendedthat silicone rubbers B.2 of the same structure, which have beenprepared from silanes with different hydrolysable groups, such as e.g.C₁-C₆ alkoxy groups or from cyclic siloxane oligomers, also be included.

Silicone graft rubbers are mentioned as a particularly preferredcomponent B.2. These may be prepared, for example, by a three-stageprocess.

In the first stage, monomers such as dimethyldichlorosilane,vinylmethyldichlorosilane or dichlorosilanes with other substituents arereacted to give cyclic oligomers (octamethylcyclotetrasiloxane ortetravinyltetramethylcyclotetrasiloxane) which can easily be purified bydistillation (see Chemie in unserer Zeit 4 (1987), 121-127).

In the second stage, cross-linked silicone rubbers are obtained fromthese cyclic oligomers by ring-opening cationic polymerisation with theaddition of mercaptopropylmethyldimethoxysilane.

In the third stage, the silicone rubbers obtained, which havegraft-active vinyl and mercapto groups, are radical graft polymerisedwith vinyl monomers (or mixtures).

Mixtures of cyclic siloxane oligomers such asoctamethylcyclotetrasiloxane and tetramethyltetravinylcyclotetrasiloxaneare preferably polymerised in emulsion in a ring-openig cationic processin the second stage. The silicone rubber is produced as a particulateemulsion.

The process is particularly preferably performed in accordance withGB-PS 1 024 014, using alkylbenzenesulfonic acids which act both ascatalyst and as emulsifier. After polymerisation, the acid isneutralised. Instead of alkylbenzenesulfonic acids, n-alkylsulfonicacids may also be used. It is also possible to use additionalco-emulsifiers in addition to the sulfonic acid.

Co-emulsifiers may be non-ionic or anionic. Suitable anionicco-emulsifiers are in particular the salts of n-alkylsulfonic oralkylbenzenesulfonic acids. Non-ionic co-emulsifiers are polyoxyethylenederivatives of fatty alcohols and fatty acids. Examples are POE(3)-lauryl alcohol, POE (20)-oleyl alcohol, POE (7)-nonyl alcohol or POE(10)-stearate. (The written form POE (number) . . . alcohol means thatthe number of ethylene oxide units corresponding to the number statedhave been added to one molecule of . . . alcohol. POE stands forpolyethylene oxide. The number is an average number).

The cross-linking and graft-active groups (vinyl and mercapto groups,see organic groups γ and δ) may be inserted into the silicone rubber byusing appropriate siloxane oligomers. Examples of these are e.g.tetramethyltetravinylcyclotetrasiloxane, orγ-mercaptopropylmethyldimethylsiloxane or its hydrolysate.

They are added to the main oligomer, e.g. octamethylcyclotetrasiloxane,in the required amount in the second, stage.

The incorporation of longer chain alkyl groups, such as e.g. ethyl,propyl or the like or the incorporation of phenyl groups may also beachieved in the same way.

Adequate cross-linking of the silicone rubber may be achieved whengroups γ and δ react with each other during emulsion polymerisation, sothat the addition of an external cross-linking agent may be unnecessary.However, a cross-linking silane may be added during the second reactionstage in order to increase the degree of cross-linking of the siliconerubber.

Branching and cross-linking may be produced by adding e.g.tetraethoxysilane or a silane of the formula

y¹—SiX₃,

wherein

X is a hydrolysable group, in particular an alkoxy group or halogen atomand

y¹ is an organic group.

Preferred silanes y¹—SiX₃ are methyltrimethoxysilane andphenyltrimethoxysilane.

The gel content is determined at 25° C. in acetone (see DE-AS 2 521 288,col. 6, lines 17 to 37). It is at least 70%, preferably 73 to 98 wt. %in the case of silicone rubbers according to the invention.

rafted silicone rubbers B may be prepared by radical graftpolymerisation, for example in the same way as in DE-PS 2 421 288.

To prepare grafted silicone rubbers, the graft monomers are radicalgraft polymerised, in the third stage, in the presence of the siliconerubber, in particular at 40 to 90° C. Graft polymerisation may beperformed in suspension, dispersion or emulsion. Continuous or batchwiseemulsion polymerisation is preferred. This graft polymerisation reactionis performed with radical initiators (e.g. peroxides, azo compounds,hydroperoxides, persulfates, perphosphates) and optionally with the useof anionic emulsifiers, e.g. carboxonium salts, sulfonates, or organicsulfates. The graft polymer is then produced with high graft yields,i.e. a high proportion of polymer formed from the graft monomers ischemically bonded to the silicone rubber. The silicone rubber hasgraft-active groups so that special measures to encourage a high degreeof grafting are superfluous.

The grafted silicone rubbers may be prepared by graft polymerisation of5 to 95 parts by wt., preferably 20 to 80 parts by wt. of a vinylmonomer or a mixture of vinyl monomers on 5 to 95, preferably 20 to 80parts by wt. of silicone rubber.

A particularly preferred vinyl monomer is styrene or methylmethacrylate. Suitable mixtures of vinyl monomers consist of 50 to 95parts by wt. of styrene, α-methylstyrene (or other alkyl or halogenring-substituted styrenes) or methyl methacrylate on the one hand and of5 to 50 parts by wt. of acrylonitrile, methacrylonitrile, C₁-C₁₈ alkylacrylates, C₁-C₁₆ alkyl methacrylates, maleic anhydride or substitutedmaleic imides on the other hand. Further vinyl monomers which may alsobe present in small amounts are acrylates of primary or secondaryaliphatic C₂-C₁₀ alcohols, preferably n-butyl acrylate or the acrylateor methacrylate of tert.-butyl alcohol, preferably t-butyl acrylate. Aparticularly preferred monomer mixture contains 30 to 40 parts by wt. ofα-methylstyrene, 52 to 62 parts by wt. of methyl methacrylate and 4 to14 parts by wt. of acrylonitrile.

The silicone rubber grafted in this way may be processed in a knownmanner, e.g. by coagulating the latices with electrolytes (salts, acidsor mixtures thereof) and then purifying and drying.

When preparing the grafted silicone rubbers, free polymers or copolymersof the graft monomers forming the graft layer are generally also formedto a certain extent, in addition to the actual graft copolymer. Here,the product obtained by polymerisation of the graft monomers in thepresence of the silicone rubber, thus actually generally including amixture of graft copolymer and free (co)polymers of the graft monomers,is called the grafted silicone rubber.

Graft polymers based on acrylates are preferably formed from

(a) 20 to 90 wt. %, with respect to the graft polymer, of acrylaterubber with a glass transition temperature of less than −20° C. as graftsubstrate and

(b) 10 to 80 wt. %, with respect to the graft polymer, of at least onepolymerisable, ethylenically unsaturated monomer (see B.1) as graftmonomers.

The acrylate rubbers (a) are preferably polymers of alkyl acrylates,optionally with up to 40 wt. %, with respect to (a), of otherpolymerisable, ethylenically unsaturated monomers. Preferredpolymerisable acrylates include C₁-C₈ alkyl esters, for example methyl,ethyl, butyl, n-octyl and 2-ethylhexyl esters; halogenated alkyl esters,preferably halogenated C₁-C₈ alkyl esters, such as chloroethyl acrylate,and mixtures of these monomers.

For cross-linking purposes, monomers with more than one polymerisabledouble bond are copolymerised. Preferred examples of cross-linkingmonomers are esters of unsaturated monocarboxylic acids with 3 to 8carbon atoms and unsaturated monohydric alcohols with 3 to 12 carbonatoms, or saturated polyols with 2 to 4 OH groups and 2 to 20 carbonatoms such as, for example, ethylene glycol dimethacrylate, allylmethacrylate, polyunsaturated heterocyclic compounds such as e.g.trivinyl and triallyl cyanurate; polyfunctional vinyl compounds such asdivinyl and trivinyl benzene; or else triallyl phosphate and diallylphthalate.

Preferred cross-linking monomers are allyl methacrylate, ethylene glycoldimethacrylate, diallyl phthalate and heterocyclic compounds whichcontain at least 3 ethylenically unsaturated groups.

Particularly preferred cross-linking monomers are the cyclic monomerstriallyl cyanurate, triallyl isocyanurate,triacrylohexahydro-s-triazine, triallyl benzene.

The amount of cross-linking monomers used is preferably 0.02 to 5, inparticular 0.05 to 2 wt. %, with respect to the rubber substrate.

In the case of cross-linking monomers with at least 3 ethylenicallyunsaturated groups it is advantageous to restrict the amount to lessthan 1 wt. % of the rubber substrate.

Preferred “other” polymerisable, ethylenically unsaturated monomerswhich may optionally be used in addition to acrylates for preparinggraft substrate B.2 are e.g. acrylonitrile, styrene, α-methylstyrene,acrylamides, vinyl-C₁-C₆ alkyl ethers, methyl methacrylate, butadiene.Preferred acrylate rubbers as graft substrate B.2 are emulsion polymerswhich have a gel content of at least 60 wt. %.

Polymers based on acrylates are generally known and can be prepared by aknown process (e.g. EP-A 244 857) or are commercially availableproducts.

The gel content of the graft substrate is determined at 25° C. in asuitable solvent (M. Hoffmann, H. Krömer, R. Kuhn, Polymeranalytik I andII, Georg Thieme-Verlag, Stuttgart, 1977).

The average particle diameter d₅₀ is the diameter, above and below which50 wt. % of the diameters of the particles are found. It can bedetermined by means of ultracentrifuge measurements (W. Scholtan, H.Lange, Kolloid, Z. und Z. Polymere 250 (1972), 782-796).

At least one copolymer or terpolymer which contains ethylene andpropylene and has only a small number of double bonds is used as anEP(D)M graft substrate (see EP-A 163 411, EP-A 244 857).

The EP(D)M rubbers used are those which have a glass transitiontemperature within the range −60 to 40° C. The rubbers have only a smallnumber of double bonds, i.e. less than 20 double bonds per 1000 carbonatoms, in particular 3 to 10 double bonds per 1000 carbon atoms.Examples of such rubbers are copolymers consisting of ethylene/propyleneand ethylene/propylene terpolymers. The latter are prepared bypolymerising at least 30 wt. % of ethylene, at least 30 wt. % ofpropylene and 0.5 to 15 wt. % of a non-conjugated, diolefinic component.The third components used are generally diolefins with at least 5 carbonatoms such as 5-ethylidenenorbornene, dicyclopentadiene,2,2,1-dicyclopentadiene and 1,4-hexadiene. Furthermore, polyalkylenamerssuch as polypentenamers, polyoctenamers, polydodecenamers or mixtures ofthese substances are also suitable. Furthermore, partially hydrogenatedpolybutadiene rubbers in which at least 70% of the residual double bondsare hydrogenated are also suitable. From among the previously mentionedrubbers, ethylene/propylene copolymers and ethylene/propyleneterpolymers (EPDM rubbers) are used in particular. As a rule, EPDMrubbers have a Mooney viscosity ML₁₋₄ (100° C.) of 25 to 120. They arecommercially available.

Graft polymers based on EP(D)M rubbers may be prepared in a variety ofways. A solution of the EP(D)M elastomer (rubber) in the monomer mixtureand (optionally) inert solvents is preferably prepared and the graftreaction is started by radical starters such as azo compounds orperoxides at elevated temperatures. The processes in DE-AS 23 02 014 andDE-OS 25 33 991 may be mentioned by way of example. It is also possibleto work in suspension, as described in U.S. Pat. No. 4,202,948.

Component C

Component C contains one or more thermoplastic vinyl (co)polymers C.1and/or polyalkylene terephthalates C.2.

Vinyl (co)polymers which are suitable for use as C.1 are polymers of atleast one monomer from the group of vinyl aromatic compounds, vinylcyanides (unsaturated nitriles), (C₁-C₈)alkyl(meth)acrylates,unsaturated carboxylic acids and derivatives (such as anhydrides andimides) of unsaturated carboxylic acids. Particularly suitable(co)polymers are those made from

C.1.1 50 to 99, preferably 60 to 80 parts by wt. of vinyl aromaticcompounds and/or ring-substituted vinyl aromatic compounds (such as, forexample, styrene, α-methylstyrene, p-methylstyrene, p-chlorostyrene)and/or (C₁-C₈)alkyl(meth)acrylates (such as e.g. methyl methacrylate,ethylmethacrylate), and

C.1.2 1 to 50, preferably 20 to 40 parts by wt. of vinyl cyanides(unsaturated nitriles) such as acrylonitrile and methacrylonitrileand/or (C₁-C₈)alkyl(meth)acrylates (such as e.g. methyl methacrylate,n-butyl acrylate, t-butyl acrylate) and/or unsaturated carboxylic acids(such as maleic acid) and/or derivatives (such as anhydrides and imides)of unsaturated carboxylic acids (for example maleic anhydride andN-phenyl-maleic imide).

(Co)polymers C.1 are resinous, thermoplastic and rubber-free.

The copolymer is particularly preferably composed of C.1.1 styrene andC.1.2 acrylonitrile.

(Co)polymers in accordance with C.1 are known and can be prepared byradical polymerisation, in particular by emulsion, suspension, solutionor bulk polymerisation. The (co)polymers preferably have molecularweights {overscore (M)}_(w), (weight average, determined by lightscattering or sedimentation) between 15 000 and 200 000.

(Co)polymers in accordance with component C.1 are frequently produced assecondary products during the graft polymerisation of component B, inparticular when large amounts of monomers B.1 are grafted onto smallamounts of rubber B.2.

The amounts of C.1 optionally also used according to the invention donot include these secondary products of graft polymerisation of B.

The polyalkylene terephthalates in component C.2 are reaction productsof aromatic dicarboxylic acids or their reactive derivatives, such asdimethyl esters or anhydrides, and aliphatic, cycloaliphatic oraraliphatic diols and also mixtures of these reaction products.

Preferred polyalkylene terephthalates contain at least 80 wt. %,preferably at least 90 wt. %, with respect to the dicarboxylic acidcomponent, of terephthalic acid groups and at least 80 wt. %, preferablyat least 90 wt. %, with respect to the diol component, of ethyleneglycol and/or butanediol-1,4 groups.

Preferred polyalkylene terephthalates may contain, in addition toterephthalates, up to 20 mol %, preferably up to 10 mol % of groups fromother aromatic or cycloaliphatic dicarboxylic acids with 8 to 14 carbonatoms or aliphatic dicarboxylic acids with 4 to 12 carbon atoms, such ase.g. groups from phthalic acid, isophthalic acid,naphthalene-2,6-dicarboxylic acid, 4,4′-diphenyldicarboxylic acid,succinic acid, adipic acid, sebacic acid, azelaic acid,cyclohexane-diacetic acid.

Preferred polyalkylene terephthalates may contain, in addition toethylene glycol or butanediol-1,4 groups, up to 20 mol %, preferably upto 10 mol %, of other aliphatic diols with 3 to 12 carbon atoms orcycloaliphatic diols with 6 to 21 carbon atoms, e.g. groups frompropanediol-1,3, 2-ethylpropanediol-1,3, neopentyl glycol,pentanediol-1,5, hexanediol-1,6, cyclohexane-dimethanol-1,4,3-ethylpentanediol-2,4, 2-methylpentanediol-2,4,2,2,4-trimethylpentanediol-1,3, 2-ethylhexanediol-1,3,2,2-diethylpropanediol-1,3, hexanediol-2,5,1,4-di(β-hydroxyethoxy)benzene, 2,2-bis-(4-hydroxycyclohexyl)-propane,2,4-dihydroxy-1,1 ,3,3-tetramethyl-cyclobutane,2,2-bis-(4-β-hydroxyethoxyphenyl)-propane and2,2-bis-(4-hydroxypropoxyphenyl)-propane DE-OS 2 407 674. 2 407 776. 2715 932).

The polyalkylene terephthalates may be branched by incorporatingrelatively small amounts of trihydric or tetrahydric alcohols ortribasic or tetrabasic carboxylic acids, e.g. in accordance with DE-OS 1900 270 and U.S. Pat. No. 3,692,744. Examples of preferred branchingagents are trimesic acid, trimellitic acid, trimethylolethaneand—propane and pentaerythritol.

Particularly preferred polyalkylene terephthalates are those which havebeen prepared solely from terephthalic acid and its reactive derivatives(e.g. its dialkyl esters) and ethylene glycol and/or butanediol-1,4, andmixtures of these polyalkylene terephthalates.

Mixtures of polyalkylene terephthalates contain 1 to 50 wt. %,preferably 1 to 30 wt. %, of polyethylene terephthalate and 50 to 99 wt.%, preferably 70 to 99 wt. %, of polybutylene terephthalate.

Preferably used polyalkylene terephthalates generally have an intrinsicviscosity of 0.4 to 1.5 dl/g, preferably 0.5 to 1.2 dl/g, measured inphenol/o-dichlorobenzene (1:1 by weight) at 25° C. in an Ubbelohdeviscometer.

Polyalkylene terephthalates can be prepared by known methods (see e.g.Kunststoff-Handbuch, vol. VIII, p. 695 et seq., Carl-Hanser-Verlag,Munich 1973).

Component D

Moulding compositions according to the invention contain, as a flameretardant, at least one phosphonate amine compound of the formula (I)

A_(3-y)—N—B_(y)  (I),

in which

wherein

R¹, R², R³ and R⁴ and also B and y are defined in the same way as givenabove.

B preferably represents, independently, hydrogen, ethyl, n-propyl oriso-propyl, which may be substituted by halogen, or a C₆-C₁₀ aryl groupwhich is unsubstituted or substituted by a C₁-C₄ alkyl group or byhalogen, in particular phenyl or naphthyl.

Alkyl in R¹, R², R³ and R⁴ preferably represents, independently, methyl,ethyl, n-propyl, iso-propyl, n-, iso-, sec. or tert.-butyl, pentyl orhexyl.

Substituted alkyl in R¹, R², R³ and R⁴ preferably represents,independently, a C₁-C₁₀ alkyl group substituted by halogen, inparticular for mono- or di-substituted methyl, ethyl, n-propyl,iso-propyl, n-, iso-, sec. or tert.-butyl, pentyl or hexyl.

R³ and R⁴, together with the carbon atom to which they are bonded,preferably form cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl, inparticular cyclopentyl or cyclohexyl.

C₆-C₁₀ aryl in R¹, R², R³ and R⁴, independently, preferably representsphenyl, naphthyl or binaphthyl, in particular o-phenyl, o-naphthyl,o-binaphthyl, which may be substituted by halogen (in general once,twice or three times).

The following are mentioned byway of example and for preference:5,5,5′,5′,5″,5″-hexamethyl-tris-(1,3,2-dioxaphosphorinane-methane)amino-2,2′,2″-trioxideof the formula (I-1)

(trial product XPM 1000, from Solutia Inc., St Louis, USA)

1,3,2-dioxaphosphorinane-2-methanamine,N-butyl-N[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)methyl]-5,5-dimethyl-,P,2-dioxide; 1,3,2-dioxaphosphorinane-2-methanamine,N-[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-5,5-dimethyl-N-phenyl-,P,2-dioxide; 1,3,2-dioxaphosphorinane-2-methanamine,N,N-dibutyl-5,5-dimethyl-, 2-oxide,1,3,2-dioxaphosphorinane-2-methanimine,N-[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-N-ethyl-5,5-dimethyl-,P,2-dioxide, 1,3,2-dioxa-phosphorinane-2-methanamine,N-butyl-N-[(5,5-di-chloromethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-5,5-di-chloromethyl-,P,2-dioxide, 1,3,2-dioxa-phosphorinane-2-methanamine,N-[(5,5-di-chloromethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-5,5-di-chloromethyl-N-phenyl-,P,2dioxide;1,3,2-dioxaphosphorinane-2-methanamine,N,N-di-(4-chlorobutyl)-5,5-dimethyl-2-oxide;1,3,2-dioxaphosphorinane-2-methanimine,N-[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methane]-N-(2chloroethyl)-5,5di-(chloromethyl)-,P2-dioxide.

Also preferred are:

compounds of the formula (I-2) or (I-3)

wherein

R¹, R², R³ and R⁴ are defined in the same way as above.

Compounds of the formula (I-2) and (I-1) are particularly preferred. Theindividual compounds mentioned above are also particularly preferred.

Compounds of the formula (I) can be prepared by the following process:

a) PCl₃ is added to a mixture of 1,3-diol derivatives, water and anorganic solvent at a temperature of 10-60° C. A 5,5-disubstituted1,3,2-dioxaphosphorinane-2-oxide of the formula (Ia) is obtained

 wherein R¹ and R₂ are defined in the same way as above,

b) after purification, the 1,3,2-dioxaphosphorinane-2-oxide is reacted,in paraformaldehyde, with an amine B_(y)NH_(3-y), wherein B and y aredefined in the same way as above,

c) after purifying again and drying, the phosphonate amine of theformula (I) is obtained.

A detailed description of the method of preparation can be found in U.S.Pat. No. 5,844,028.

Component E

Fluorinated polyolefins E have high molecular weights and have glasstransition temperatures higher than −30° C., generally higher than 100°C., and fluorine contents of preferably 65 to 76, in particular 70 to 76wt. %, average particle diameters d₅₀ of 0.05 to 1 000, preferably 0.08to 20 μm. Fluorinated polyolefins E generally have a density of 1.2 to2.3 g/cm³. Preferred fluorinated polyolefins E arepolytetrafluoroethylene, polyvinylidene fluoride,tetrafluoroethylene/hexafluoropropylene and ethylene/tetrafluoroethylenecopolymers. The fluorinated polyolefins are known (see “Vinyl andRelated Polymers” by Schildknecht, John Wiley & Sons, Inc., New York,1962, pages 484—494; “Fluorpolymers” by Wall, Wiley-Interscience, JohnWiley & Sons, Inc., New York, vol. 13, 1970, pages 623-654; “ModemPlastics Encyclopedia”, 1970-1971, vol. 47, no. 10A, October 1970,McGraw-Hill, Inc., New York, pages 134 and 774; “Modem PlasticsEncyclopedia”, 1975-1976, October 1975, vol. 52, no. 10A, McGraw-Hill,Inc., New York, pages 27, 28 and 472 and U.S. Pat. No. 3,671,487,3,723,373 and 3,838,092).

They can be prepared by known processes, that is, for example, bypolymerising tetrafluoroethylene in aqueous medium with a freeradical-producing catalyst, for example sodium, potassium or ammoniumperoxydisulfate, at pressures of 7 to 71 kg/cm² and at temperatures of 0to 200° C., preferably at temperatures of 20 to 100° C. (For moredetails, see e.g. U.S. Pat. No. 2,393,967). Depending on the initialform, the density of these materials is between 1.2 and 2.3 g/cm³ andthe average particle size is between 0.5 and 1 000 μm.

According to the invention, preferred fluorinated polyolefins E aretetrafluoroethylene polymers with average particle diameters of 0.05 to20 μm, preferably 0.08 to 10 μm, and a density of 1.2 to 1.9 g/cm³ andare preferably used in the form of a coagulated mixture of emulsions oftetrafluoroethylene polymer E and emulsions of the graft polymer.

Further preparations which are preferred according to the invention arefluorinated polyolefins E:

E.1) as a coagulated mixture with at least one of components A to C,wherein the fluorinated polymer E or polyolefin mixture as an emulsionis mixed with at least one emulsion of the components A to C and is thencoagulated or

E.2) as a pre-compound with at least one of components A to C, whereinthe fluorinated polyolefin E as a powder is mixed with a powder orgranules of at least one of the components A to C and is compounded inthe molten state, in general at temperatures of 208° C. to 330° C. inconventional equipment such as internal compounders, extruders ortwin-shaft screws.

Preferred preparations of fluorinated polyolefin E are coagulatedmixtures with a graft polymer B or a vinyl (co)polymer C.

Fluorinated polyolefins E which are suitable for use in powdered formare tetrafluoroethylene polymers with average diameters of 100 to 1 000μm and densities of 2.0 g/cm³ to 2.3 g/cm³.

To prepare a coagulated mixture of a graft polymer and component E, anaqueous emulsion (latex) of a graft polymer B is first mixed with afinely divided emulsion of a tetrafluoroethylene polymer E; suitabletetrafluoroethylene polymer emulsions normally have solids contents of30 to 70 wt. %, preferably 50 to 60 wt. %, in particular 30 to 35 wt. %.

The data relating to amounts in the description of components A, B and Cdoes not contain the proportion of graft polymer, vinyl (co)polymer orpolycarbonate for the coagulated mixture in accordance with E.1) andE.2).

The ratio by weight of graft polymer B or (co)polymer to fluorinatedpolyolefin E in the emulsion mixture is 95:5 to 60:40, preferably 90:10to 50:50. Then, the emulsion mixture is coagulated in a known manner,for example by spray-drying, freeze-drying or coagulation by means ofadding inorganic or organic salts, acids, bases or water-miscibleorganic solvents such as alcohols or ketones, preferably at temperaturesof 20 to 150° C., in particular 50 to 100° C. If required, the mixturemay be dried at 50 to 200° C., preferably 70 to 100° C.

Suitable tetrafluoroethylene polymer emulsions are commerciallyavailable products and are sold, for example, by DuPont as Teflon® 30 N.

Moulding compositions according to the invention may contain at leastone of the conventional additives such as lubricants and mould-releaseagents, nucleating agents, antistatic agents, stabilisers or colorantsand pigments.

Moulding compositions according to the invention may contain up to 35wt. %, with respect to the entire moulding composition, of a further,optionally synergistic, flame retardant. Examples of further flameretardants which may be mentioned are organic phosphorus compounds suchas triphenyl phosphate or m-phenylene-bis-(diphenylphosphate), organichalogenated compounds such as decabromobisphenyl ether,tetrabromobisphenol, inorganic halogen compounds such as ammoniumbromide, nitrogen compounds such as melamine, melamine/formaldehyderesins, inorganic hydroxide compounds such as Mg or Al hydroxide,inorganic compounds such as antimony oxides, hydroxoantimonate,zirconium oxide, zirconium hydroxide, molybdenum oxide, ammoniummolybdate, zinc borate, ammonium borate, barium metaborate, talc,silicate, silicon oxide and tin oxide and also siloxane compounds.

Furthermore, phosphorus compounds of the formula (VI) are suitable asflame retardants,

in which

R¹³, R¹⁴ and R¹⁵, independently, represent an optionally halogenatedC₁-C₈ alkyl or an optionally halogenated and/or alkylated C₅ or C₆cycloalky or an optionally halogenated and/or alkylated and/oraralkylated C₆-C₃₀ aryl group and

“n” and “l”, independently, are 0 or 1.

These phosphorus compounds are generally known (see for example,Ullmann, Enzyklopädie der technischen Chemie, vol. 18, pages 301 etseq., 1979 and EP-A 345 522). Aralkylated phosphorus compounds aredescribed, for example, in DE-OS 38 24 356.

Optionally halogenated C₁-C₈ alkyl groups in accordance with (VI) maycontain one or more halogen atoms and be linear or branched. Examples ofalkyl groups are chloroethyl, 2-chloropropyl, 2,3-dibromopropyl, butyl,methyl or octyl.

Optionally halogenated and/or alkylated C₅ or C₆ cycloalkyl groups inaccordance with (VI) are optionally singly or multiply halogenatedand/or alkylated C₅ or C₆ cycloalkyl groups, that is e.g. cyclopentyl,cyclohexyl, 3,3,5-trimethylcyclohexyl and fully chlorinated cyclohexyl.

Optionally halogenated and/or alkylated and/or aralkylated C₆-C₃₀ arylgroups in accordance with (VI) are optionally mononuclear orpolynuclear, singly or multiply halogenated and/or alkylated and/oraralkylated groups, e.g. chlorophenyl, bromophenyl, pentachlorophenyl,pentabromophenyl, phenyl, cresyl, isopropylphenyl, benzyl-substitutedphenyl and naphthyl.

R¹³, R¹⁴ and R¹⁵ preferably represent, independently, methyl, ethyl,butyl, octyl, phenyl, cresyl, cumyl or naphthyl. R¹³, R¹⁴ and R¹⁵,independently, represent in particular methyl, ethyl or butyl or phenylwhich is optionally substituted by methyl and/or ethyl.

Phosphorus compounds in accordance with formula (VI) which may be usedaccording to the invention are e.g. tributyl phosphate,tris-(2-chloroethyl)phosphate, tris-(2,3-dibromopropyl)phosphate,triphenyl phosphate, tricresyl phosphate, diphenylcresyl phosphate,diphenyloctyl phosphate, diphenyl-2-ethylcresyl phosphate,tri-(isopropylphenyl)phosphate, tris-(p-benzylphenyl)phosphate,triphenylphosphine oxide, dimethyl methanephosphonate, dipentylmethanephosphonate and diethyl phenylphosphonate.

Suitable flame retardants are also dimeric and oligomeric phosphatessuch as are described, for example, in EP-A-0 363 608.

Moulding compositions according to the invention may also containphosphorus compounds in accordance with formula (VII) as flameretardants

In the formula, R¹⁶, R¹⁷, R¹⁸ and R¹⁹, independently, each representoptionally halogenated C₁-C₈ alkyl, C₅-C₆ cycloalkyl, C₆-C₂₀ aryl orC₇-C₁₂ aralkyl groups.

R¹⁶, R¹⁷, R¹⁸ and R¹⁹, independently, preferably represent C₁-C₄ alkyl,phenyl, naphthyl or phenyl-C₁-C₄-alkyl groups. Aromatic groups R¹⁶, R¹⁷,R¹⁸ and R¹⁹ may for their part be substituted with halogen atoms and/oralkyl groups, preferably chlorine, bromine and/or C₁-C₄ alkyl groups.Particularly preferred aryl groups are cresyl, phenyl, xylenyl,propylphenyl or butylphenyl and also the corresponding brominated andchlorinated derivatives thereof.

X in formula (VII) represents a mononuclear or polynuclear aromaticgroup with 6 to 30 carbon atoms. This is preferably derived fromdiphenols of the formula (III). Diphenylphenol, bisphenol A, resorcinolor hydroquinone or their chlorinated or brominated derivatives areparticularly preferred.

n in formula (VII) may, independently, be 0 or 1; n is preferably equalto 1.

k has a value from 0 to 30 and preferably has an average value from 0.3to 20, in particular 0.5 to 10, specifically 0.5 to 6.

Mixtures of 10 to 90 wt. %, preferably 12 to 40 wt. %, of at least onemonophosphorus compound of the formula (VI) and at least one oligomericphosphorus compound, for example a mixture of oligomeric phosphoruscompounds such as those described in EP-A-363 608 and phosphoruscompounds in accordance with formula (VII) in amounts of 10 to 90 wt. %,preferably 60 to 88 wt. %, with respect to the total amount ofphosphorus compounds, may also be used.

Monophosphorus compounds of the formula (VI) are in particular tributylphosphate, tris-(2-chloroethyl)phosphate,tris-(2,3-dibromopropyl)phosphate, triphenyl phosphate, tricresylphosphate, diphenylcresyl phosphate, diphenyloctyl phosphate,diphenyl-2-ethylcresyl phosphate, tri-(isopropylphenyl)phosphate,halogen-substituted aryl phosphates, dimethyl methylphosphonate,diphenyl methylphosphonate and diethyl phenylphosphonate,triphenylphosphine oxide or tricresylphosphine oxide.

The mixtures of monomeric and oligomeric phosphorus compounds of theformula (VII) have average k values of 0.3 to 20, preferably 0.5 to 10,in particular 0.5 to 6.

The phosphorus compounds mentioned are known (e.g. EP-A-363 608, EP-A640655) or can be prepared in a similar manner by known methods (e.g.Ullmanns Encyklopädie der technischen Chemie, vol. 18, p. 301 et seq.,1979; Houben-Weyl, Methoden der organischen Chemie, vol. 12/1, p. 43;Beilstein vol. 6, p. 177).

Moulding compositions according to the invention containing components Ato E and optionally further known additives such as stabilisers,colorants, pigments, lubricants and mould release agents, nucleatingagents and antistatic agents, are prepared by mixing the relevantconstituents in a known manner and melt compounding and melt extrudingat temperatures of 200° C. to 300° C. in conventional equipment such asinternal compounders, extruders and twin-shaft screws, wherein componentE is preferably used in the form of the coagulated mixture mentionedabove.

Mixing the individual constituents may take place in a known mannereither in sequence or simultaneously, in fact either at about 20° C.(room temperature) or at a higher temperature.

The invention therefore also provides a process for preparing themoulding compositions.

Due to their exceptional flame resistance and good mechanicalproperties, thermoplastic blends according to the invention are suitablefor producing moulded articles of any type, in particular those withhigh demands relating to resistance to breaking and resistance tochemicals.

Blends according to the present invention may be used to produce mouldedarticles of any type. In particular, moulded articles may be produced byinjection moulding. Examples of moulded articles which can be producedare: housing sections of any type, e.g. for domestic equipment such asjuice presses, coffee machines, mixers, for office machines such asmonitors, printers, copiers or cladding for the construction sector andparts for the car sector. They can also be used in the electricalengineering area because they have very good electrical properties.

Furthermore, blends according to the invention may be used, for example,to produce the following moulded articles or moulded parts:

Internal structural parts for rail vehicles, hub caps, housings forelectrical equipment containing small transformers, housings forequipment for information distribution and transmission, housings andcovers for medical purposes, massage equipment and housings therefor,toy vehicles for children, two-dimensional wall panels, housings forsafety devices, rear spoilers, thermally insulated transport containers,devices for housing or caring for small animals, moulded parts forsanitary and bath fittings, cover grids for ventilation openings,moulded parts for summerhouses and garden sheds, housings for gardenequipment.

Another form of processing is the production of moulded articles bythermoforming from previously produced sheets or films.

Therefore, the present invention also provides use of blends accordingto the invention to produce moulded articles of any type, preferably thearticles mentioned above, and the moulded articles made from mouldingcompositions according to the invention.

EXAMPLES Component A

Linear polycarbonate based on bisphenol A with a relative solutionviscosity of 1.252 measured in CH₂Cl₂ as solvent at 25° C. and at aconcentration of 0.5 g/100 ml.

Component B

B.1 Silicone Graft Rubber

1. Preparing the Silicone Rubber Emulsion

38.4 parts by wt. of octamethylcyclotetrasiloxane, 1.2 parts by wt. oftetramethyltetravinylcyclotetrasiloxane and 1 part by wt. ofmercaptopropylmethyldimethoxysilane are stirred together. 0.5 parts bywt. of dodecylbenzenesulfonic acid are added, then 58.4 parts by wt. ofwater are added over the course of one hour. The mixture is intensivelystirred. The pre-emulsion is homogenised twice at 200 bar, using a highpressure emulsifying machine. Another 0.5 parts by wt. ofdodecylbenzenesulfonic acid are added. The emulsion is stirred for 2hours at 85° C. and then for 36 hours at 20° C. The mixture isneutralised using 5N NaOH. A stable emulsion with a solids content ofabout 36 wt. % is obtained. The polymer has a gel content of 82 wt. %,measured in toluene; the average particle diameter d₅₀ is 300 nm.

2. Preparing the Grafted Silicone Rubber

The following are initially introduced into a reactor:

2107 parts by wt. of latex according to 1) and 1073 parts by wt. ofwater

After initiating reaction with a solution of 7.5 parts by wt. ofpotassium peroxydisulfate in 195 parts by wt. of water at 65° C., eachof the following solutions are supplied uniformly over the course of 4hours in order to prepare the graft rubber:

Solution 1: 540 parts by wt. of styrene and 210 parts by wt. ofacrylonitrile;

Solution 2: 375 parts by wt. of water and 15 parts by wt. of the sodiumsalt of C₁₄-C₁₈ alkylsulfonic acids.

Then the mixture is polymerised for 6 hours at 65° C. A latex with asolids content of about 33 wt. % is obtained.

After coagulation with an aqueous magnesium chloride/acetic acidsolution, filtration and drying under vacuum, the graft polymers areobtained in the form of a white powder.

B.2 Acrylate Graft Rubber

A graft polymer of 40 parts by wt. of a copolymer of styrene andacrylonitrile in the ratio of 72:28 on 60 parts by wt. of particulatecross-linked polyacrylate rubber (mean particle diameter d₅₀=0.5 μm)prepared by emulsion polymerisation.

B.3 EPDM Graft Rubber

Graft polymer of 50 parts by wt. of a copolymer of styrene andacrylonitrile in the ratio of 72:28 on 50 parts by wt. of cross-linkedEPDM rubber from the Uniroyal Chemical Company, commercial name Royaltuf372 P20.

B.4 Graft polymer of 45 parts by wt. of a copolymer of styrene andacrylonitrile in the ratio of 72:28 on 55 parts by wt. of particulatecross-linked polybutadiene rubber (mean particle diameter d₅₀=0.40 μm),prepared by emulsion polymerisation.

Component C

Styrene/acrylonitrile copolymer with a styrene/acrylonitrile ratio byweight of 72:28 and an intrinsic viscosity of 0.55 dl/g (measured indimethylformamide at 20° C.).

Component D

A phosphonate amine of the formula

(XPM 1000 development product from Solutia Inc., St Louis, Mo.).

Component E

Batch SAN/Teflon in the ratio by weight of 1:1: Blendex 446, GeneralElectric, N.Y. USA.

Preparing and Testing Moulding Compositions According to the Invention

The components were mixed in a 3 1 internal compounder. The mouldedarticles were prepared at 260° C. on an injection moulding machine ofthe Arburg 270 E type.

The heat resistance according to Vicat B was determined in accordancewith DIN 53 460 (ISO 306) using rods with the dimensions 80×10×4 mm.

The stress crack behaviour (ESC behaviour) was investigated using rodswith the dimensions 80×10×4 mm, processing temperature 260° C. A mixtureof 60 vol. % toluene and 40 vol. % isopropanol was used as the testmedium. The specimens were pre-stretched using an arc-shaped jig(pre-stretching as a percentage) and stored at room temperature in thetest medium. The stress crack behaviour is assessed by the production ofcracks or a fracture, as a function of the pre-stretching in the testmedium.

The MVI (240/5) [cm³/10 min] was measured in accordance with ISO 1133.

The viscosity was measured in accordance with DIN 54 811.

As can be seen from the table given below, moulding compositionsaccording to the invention are characterised by a beneficial combinationof properties consisting of flame-resistance and mechanical properties.Surprisingly, the fundamental rubber characteristics of notched impactresistance and ESC behaviour, which is a measure of the resistance tochemicals, are modified when compared with the prior art (diene rubber)and crucially improved. In the resistance to stress crack test, themoulding compositions according to the invention withstood fracturingfor substantially longer, which is important for critical applications(arts with complicated geometries).

TABLE Moulding compositions and their properties 4 Example 1 2 3comparison Components (parts by wt.) 67.60 67.60 67.60 67.60 A B.1 10.50— — — B.2 — 10.50 — — B.3 — — 10.50 — B.4 — — — 10.50 C 8.80 8.80 8.808.80 D 11.90 11.90 11.90 11.90 E 0.8 0.8 0.8 0.8 Mould release agent 0.40.4 0.4 0.4 Properties Vicat B 120 (ISO 306) 116 116 116 116 (° C.) ESCbehaviour AL* 2.4 2.4 2.4 2.0 Fracture at ε_(x) (%) (10 min) (5 min) (5min) (5 min) UL 94V 3.2 mm V-0 V-0 V-0 V-0 MVI [cm³/10 min) 12.8 25.015.0 12.2 Viscosity function 116.7 94.1 90.3 117.4 260° C./1500 s⁻¹ *AL= attacked

What is claimed is:
 1. Blends which contain A) polycarbonate and/orpolyestercarbonate, B) at least one rubber-elastic graft polymer,selected from the group consisting of silicone, EP(D)M and acrylaterubbers as graft substrate, C) optionally, at least one thermoplasticpolymer, selected from the group consisting of C.1 vinyl (co)polymersand C.2 polyalkylene terephthalates and D) 0.1 to 30 parts by wt. (withrespect to the entire mixture) of a phosphonate amine of the generalformula (I) A_(3-y)—N—B_(y)  (I),  in which A represents a group of theformula (IIa)

R¹ and R2, independently, represent an unsubstituted or substitutedC₁-C₁₀ alkyl group or an unsubstituted or substituted C6-C₁₀ aryl group,R³ and R⁴, independently, represent an unsubstituted or substitutedC₁-C₁₀ alkyl group or an unsubstituted or substituted C₆-C₁₀ aryl groupor R³ and R⁴ together represent an unsubstituted or substituted C₃-C₁₀alkylene group, y has the numerical value 0, 1 or 2 and B independently,represents hydrogen, an optionally halogenated C₂-C8 alkyl group, or anunsubstituted or substituted C₆-C₁₀ aryl group.
 2. Blends in accordancewith claim 1, containing 40-99 parts by wt. of component A, 0.5-60 partsby wt. of component B, 0-45 parts by wt. of component C, 0.1-25 parts bywt. of component D, and 0-5 parts by wt. of a fluorinated polyolefin. 3.Blends according to claim 2 containing 2 to 20 parts by wt. of D. 4.Blends according to claim 1 wherein component B) is at least one graftpolymer selected from the group consisting of B.1 5 to 95 wt. % of atleast one vinyl monomer on B.2 95 to 5 wt. % of one or more graftsubstrates with glass transition temperatures of <10° C. selected fromthe group consisting of silicone, acrylate and EP(D)M rubbers.
 5. Blendsaccording to claim 4, wherein vinyl monomers B.1 are selected from:B.1.1 50 to 99 parts by wt. of at least one member selected from thegroup consisting of vinyl aromatic compounds, ring-substituted vinylaromatic compounds, and C₁-C₈ alkyl methacrylates, and B.1.2 1 to 50parts by wt. of at least one member selected from the group consistingof vinyl cyanides, C₁-C₈ alkyl(meth)acrylates, anhydrides of unsaturatedcarboxylic acids, and imides of unsaturated carboxylic acids.
 6. Blendsaccording to claim 5, wherein B.1.1 is at least one member selected fromthe group consisting of styrene, α-methylstyrene and methyl methacrylateand B.1.2 is at least one member selected from the group consisting ofacrylonitrile, methacrylonitrile, maleic anhydride and methylmethacrylate.
 7. Blends according to claim 1 wherein component C.1consists of vinyl (co)polymers prepared from at least one monomerselected from the group consisting of vinyl aromatic compounds, vinylcyanides, C₁-C₈ alkyl(meth)acrylates, unsaturated carboxylic acids,anhydrides of unsaturated carboxylic acids, and imides of unsaturatedcarboxylic acids.
 8. Blends according to claim 1 wherein phosphonateamine is a member selected from the group consisting of5,5,5′,5′,5″,5″-hexamethyl-tris-(1,3,2-dioxaphosphorinane-methane)-amino-2,2′,2″-trioxide,1,3,2-dioxaphosphorinane-2-methanamine,N-butyl-N[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-5,5-dimethyl-,P,2-dioxide; 1,3,2-dioxaphosphorinane-2-methanamine,N-[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-5,5-dimethyl-N-phenyl-P,2-dioxide; 1,3,2-dioxaphosphorinane-2-methanamine,N,N-dibutyl-5,5-dimethyl-, 2-oxide,1,3,2-dioxaphosphorinane-2-methanimine,N-[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-N-ethyl-5,5-dimethyl-,P,2-dioxide, 1,3,2-dioxa-phosphorinane-2-methanamine,N-butyl-N-[(5,5-dichloromethyl-1,3,2-dioxaphosphorinan-2-yl)-methyl]-5,5-dichloromethyl-,P,2-dioxide, 1,3,2-dioxa-phosphorinane-2-methanamine,N-[(5,5-di-chloromethyl-1,3,2-dioxa-phosphorinan-2-yl)-methyl]-5,5-di-chloromethyl-N-phenyl-,P,2-dioxide; 1,3,2-dioxaphosphorinane-2-methanamine,N,N-di-(4-chlorobutyl)-5,5-dimethyl-2-oxide;1,3,2-dioxaphosphorinane-2-methanimine andN-[(5,5-dimethyl-1,3,2-dioxaphosphorinan-2-yl)-methane]-N-(2-chloroethyl)-5,5-di-(chloromethyl)-,P2-dioxide.
 9. Blends according to claim 1 further containing at leastone additive selected from the group consisting of lubricants, mouldrelease agents, nucleating agents, antistatic agents, stabilisers,colorants and pigments.
 10. Blends according to claim 1 furthercontaining a flame retardant which is different from component D.
 11. Amethod of using the blend of claim 1 comprising producing a moldedarticle.
 12. A molded article comprising the blend of claim 1.